Introduction Thromboemboembolic event (TEE) remains the main perioperative challenge in addition to potential intracranial hemorrhage (ICH) in stent-assisted repair of intracranial aneurysms (SARIA) or flow diversions (FD) for cerebral aneurysm. There are no standard antiplatelet strategies. Based on the data, antiplatelets effect are more pronounce within the first 4 hours after administration.

Objectives To evaluate if the acute loading doses of aspirin and clopidogrel (LDAC) followed by long-term antiplatelets regimen in SARIA have any immediate and long-term effects on TEE and ICH.

Methods Consecutive patients underwent SARIA using loading dose of aspirin 324 mg (4 baby aspirin) and clopidogrel 300 mg 2 to 4 hours before the procedure were enrolled from 2011 to 2022 prospectively. Continuation of both full dose aspirin and clopidogrel for 30 days followed by 81 mf of aspirin and 75 mg of clopidogrel for additional 9 months, and after 9 months, 325 mg aspirin only. Patients demographics including intra-operative and post operative events were recorded. Outcome was measured using modified Rankin Scale (mRS) score.

Results 112 patients (baseline mRS 2 in 6, mRS3 in 1) with mean age of 53 ± 13 underwent SARIA (7 ruptured and 55 symptomatic). Aneurysms are; Right internal carotid artery (ICA) 27, left ICA 35, middle cerebral artery 25, basilar artery 19 and anterior communicating artery 6. Stent deployment was achieved in all. There was no intra-operative rupture or ICH. A small perioperative left hemispheric subarachnoid hemorrhage was observed on a right MCA aneurysm on day 3 after discharged, which resolved spontaneously without requirement of stopping antiplatelet. Intra-operative asymptomatic stent thrombosis developed in one; treated with intraarterial integrilin followed by intravenous infusion resulting. Post-operative symptomatic TEE were observed in 2 cases (2%); first was on day 2 in a giant right ICA aneurysm with NIHSS 6 and who recovered completely (NIHSS 0, mRS 1) in 90 days. 2^nd event was a visual distortion and diplopia (NIHSS 0) developed on day 2 in a basilar artery aneurysm, which resolved completely and return to her nursing job. All ruptured and symptomatic aneurysms were secured and there are no subarachnoid hemorrhages during long follow-up period. Immediate complete and near complete obliteration of aneurysm was observed in 72% and subtotal in 28%. There was no mortality or permanent disability in our series. 90 days mRS 0 and 1 was observed in 98 (92.5%) and mRS 2 in 6 (5.7%) at baseline, mRS 3 in 2 (1.9%); one LICA ruptured with initial H&H IV improved to IIIB, and treated. Second case baseline mRS 3 from previously ruptured and clipped RMCA aneurysm. 12 months mRS 0 and 1 in 98(92.5%), mRS 2 in 7 (6.6%) and mRS 3 in 1 at her base line.

Conclusions Our study revealed that LDAC in SARIA is associated with a low immediate and long-term TEE without added risk of ICH and good outcome with no mortality or permanent disability. Our antiplatelets regimen may be an option in SARIA. Further studies are required to evaluate our antiplatelets strategies on FD.

Disclosures Y. Lodi: None. V. Reddy: None.